The Rounds whose delusion was destroyed were cornered and
sought the way of self-justification to the fantasy of the nature of human race and the illusion of
good and evil.
The delusion of human nature is a belief like; "A human being has a combative instinct.
Therefore, human beings are always opposed and fight against each other.
This is a law of nature called the struggle for existence."
No matter how many people were killed, if you put the blame on a fighting instinct
or the battle for existence,
don't you feel that self-justification becomes somehow possible?

It is just an extension of the belief "People are living beings who automatically get into conflict"
that the Rounds brought up for a long time.